Oil seal for forklift differential, forklift differential, and working method of oil seal

Abstract

The present application belongs to the technical field of sealing engineering elements, and particularly relates to an oil seal for a forklift differential, a forklift differential, and a working method of the oil seal. The oil seal for the forklift differential comprises a sealing lip, an inner wall of the sealing lip comprising a first inclined surface and a second inclined surface, and a plurality of memory metal sheets, each of the memory metal sheets being obliquely arranged and uniformly distributed along the circumference of the first inclined surface to form a straight oil return line. When the temperature of the gear oil rises, the memory metal sheets bend into an "S" shape, and adjacent memory metal sheets are connected end to end to form a wavy oil return line, so that the gear oil flows along the wavy oil return line. The oil seal for the forklift differential, the forklift differential, and the working method of the oil seal use memory metal sheets as the oil return line. When the temperature rises, the memory metal sheets deform from a straight oil return line into a wavy oil return line, so that the gear oil can flow along the wavy oil return line. In this flow mode, cracking products are not easy to accumulate at the lip.

Description

Technical Field

[0001] This invention belongs to the technical field of sealing engineering components, specifically relating to sealing engineering components with at least one sealing lip, and particularly to an oil seal for a forklift differential, a forklift differential, and a method for operating the oil seal. Background Technology

[0002] Forklift operations typically involve starting, stopping, lifting, and steering, and the differential will be subjected to huge torque and impact loads when in operation.

[0003] In related technologies, differentials typically use oil seals with a straight lip return line. However, the frequent load cycles during forklift operation cause severe pressure fluctuations and heat buildup inside the differential, leading to a high temperature rise in the internal gear oil. Commonly used gear oils are prone to cracking at high temperatures, and these cracked products accumulate on the lip surface, damaging the original seal and ultimately causing leakage. Compared to oil seals used in other vehicles, the forklift differential oil seal shows significant damage because the forklift's operating conditions prevent its motor from reaching high speeds, thus hindering gear oil splash lubrication at high temperatures and leading to the accumulation of gear oil cracked products.

[0004] Therefore, how to solve the technical problem that gear oil cracking products tend to accumulate on the lip surface and thus destroy the seal morphology under high temperature conditions in oil seals with straight return oil lines is a problem that urgently needs to be solved by those skilled in the art.

[0005] It should be noted that the information disclosed in this background section is only for understanding the background technology of the present application concept, and therefore, the above description is not considered to constitute prior art information. Summary of the Invention

[0006] This disclosure provides at least one embodiment of an oil seal for a forklift differential, a forklift differential, and a method for operating the oil seal.

[0007] In a first aspect, this disclosure provides an oil seal for a forklift differential, comprising: a sealing lip, the inner wall of which includes: a first inclined surface and a second inclined surface; a plurality of shape memory metal sheets, each of which is inclined and evenly distributed along the circumference of the first inclined surface to form a straight oil return line; wherein when the temperature of the gear oil rises, the shape memory metal sheets bend into an "S" shape, and adjacent shape memory metal sheets are connected end to end to form a wavy oil return line, so that the gear oil flows along the wavy oil return line.

[0008] In one alternative embodiment, the middle portion of the shape memory metal sheet is connected to the first inclined surface; when the temperature of the gear oil rises, the two ends of the shape memory metal sheet bend in opposite directions to form an "S" shape.

[0009] In one optional embodiment, the outer wall of the sealing lip is provided with an annular receiving groove; an annular elastic element is sleeved inside the annular receiving groove, so that the inner wall of the sealing lip abuts against the central axis to seal.

[0010] In one alternative embodiment, when forming a straight return oil line, the tilt angle α of the memory metal sheet is between 45-60°; and the distance H1 between the inner end of the memory metal sheet and the lip of the sealing lip is between 0.5-1.5 mm.

[0011] In one alternative embodiment, when forming a wavy return oil line, the distance H2 between the inner peak of the memory metal sheet and the lip of the sealing lip is 2-5 mm.

[0012] In one optional embodiment, a dustproof lip is provided on the outer side of the sealing lip; a gear oil storage cavity is provided between the dustproof lip and the sealing lip.

[0013] Secondly, this disclosure provides a forklift differential, including: a differential body having a mounting hole for a motor shaft to pass through; and an oil seal for the forklift differential disposed within the mounting hole of the differential body.

[0014] Thirdly, this disclosure also provides a method for operating an oil seal for a forklift differential, comprising: a plurality of inclined shape memory metal sheets are uniformly arranged along the circumference of the first inclined surface of the sealing lip to form a straight oil return line; when the temperature of the gear oil rises, each shape memory metal sheet deforms to connect adjacent shape memory metal sheets end to end to form a wavy oil return line.

[0015] In one optional embodiment, the method of forming a wavy oil return line by deforming adjacent memory metal sheets to connect end to end when the gear oil temperature rises includes: connecting the middle part of the memory metal sheet to a first inclined surface; forming an "S" shape by bending the two ends of the memory metal sheet in the opposite direction when the gear oil temperature rises; and forming a wavy oil return line by connecting adjacent "S" shaped memory metal sheets end to end.

[0016] In one alternative embodiment, the method of forming an "S" shape by bending the shape memory metal sheet in the opposite direction at both ends when the temperature of the gear oil rises includes: when the temperature of the gear oil rises, both ends of the shape memory metal sheet are bent inward to form an "S" shape.

[0017] The beneficial effects of this invention are that the oil seal for the forklift differential, the forklift differential, and the working method of the oil seal are achieved by setting a return oil line whose shape can change with temperature. When the temperature rises, the shape memory metal sheet deforms, changing from a straight return oil line to a wavy return oil line, allowing the gear oil to flow along the wavy return oil line. Under this flow mode, cracked products are less likely to accumulate at the lip. In particular, this solution does not directly use a wavy return oil line because a straight return oil line can provide a more direct oil flow path, reduce flow resistance, and improve return oil efficiency.

[0018] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of an oil seal for a forklift differential provided in an embodiment of the present disclosure;

[0022] Figure 2 This is a schematic diagram of a linear oil return line provided in an embodiment of the present disclosure;

[0023] Figure 3 This is a schematic diagram of a wavy return oil line provided in an embodiment of the present disclosure;

[0024] Figure 4 This is a schematic diagram of the structure of a ring-shaped elastic element provided in an embodiment of the present disclosure;

[0025] Figure 5 This is a schematic diagram of a structure in which a sealing lip abuts against a central shaft, according to an embodiment of the present disclosure.

[0026] Figure 6 This is a schematic diagram of the structure of a dustproof lip provided in an embodiment of the present disclosure;

[0027] Figure 7 This is a schematic diagram of a differential provided in an embodiment of the present disclosure.

[0028] In the picture:

[0029] 1. Sealing lip; 11. First inclined surface; 12. Second inclined surface; 13. Annular receiving groove; 14. Annular elastic element; 15. Lip; 2. Straight oil return line; 21. Memory metal sheet; 211. Middle part; 212. Inner end; 213. Inner peak; 3. Wavy oil return line; 4. Central shaft; 5. Dustproof lip; 6. Gear oil temporary storage chamber; 7. Differential body; 8. Motor. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the figures, the thickness of parts may be exaggerated or reduced for the purpose of effectively depicting the technical content.

[0032] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0033] like Figures 1 to 3 As shown, at least one embodiment provides an oil seal for a forklift differential, comprising: a sealing lip 1, the inner wall of which includes: a first inclined surface 11 and a second inclined surface 12; a plurality of shape memory metal sheets 21, each shape memory metal sheet 21 being inclined and evenly distributed along the circumference of the first inclined surface 11 to form a straight oil return line 2; wherein when the temperature of the gear oil rises, the shape memory metal sheets 21 bend into an "S" shape, and adjacent shape memory metal sheets 21 are connected end to end to form a wavy oil return line 3, so that the gear oil flows along the wavy oil return line 3.

[0034] Specifically, the channel between adjacent memory metal sheets 21 is the return oil channel of the straight oil return line 2; when the gear oil temperature is low, the straight oil return line 2 formed by the memory metal sheets 21 of the oil seal can make the oil return from the working parts more smoothly; the straight oil return line 2 is used because the flow resistance of the oil is large at low temperature, and the flow speed of the oil becomes the key factor affecting the return oil efficiency.

[0035] In this embodiment, the straight return oil line 2, due to its simple geometry, reduces bends and corners in the flow path, thereby reducing flow resistance and effectively reducing the generation of turbulence and eddies. As the differential's operating time increases, the gear oil temperature rises. At this time, the shape memory metal sheet 21 is heated and deforms into a wavy return oil line 3, allowing the gear oil to flow along the wavy return oil line 3, resulting in a stronger pumping effect. When the oil flows at high speed, the crests and troughs of the wavy return oil line 3 can effectively guide the oil flow, allowing the gear oil to flow along the wavy return oil line 3. Under this flow mode, cracked products are less likely to accumulate at the lip. The reason why this solution does not directly use the wavy return oil line 3 is that when the gear oil is at a low temperature, the oil will generate additional flow resistance when passing through the crests and troughs. This resistance may lead to poor oil flow and affect the return oil efficiency. In contrast, the straight return oil line 2 has less flow resistance when the gear oil is at a low temperature due to its simple straight design.

[0036] like Figure 3 As shown, in some embodiments, the middle portion 211 of the shape memory metal sheet 21 is connected to the first inclined surface 11; when the temperature of the gear oil rises, the two ends of the shape memory metal sheet 21 bend in opposite directions to form an "S" shape.

[0037] Specifically, a locking block is provided in the middle part 211 of the memory metal sheet 21, and a slot adapted to the locking block is provided on the first inclined surface 11. The locking block is inserted into the slot and is interference-fitted, that is, the locking block is fixed and will not rotate.

[0038] In this embodiment, the middle part 211 of the shape memory metal sheet 21 is connected to the first inclined surface 11 for fixing, and the two ends of the shape memory metal sheet 21 are not fixed, so that the shape memory metal sheet 21 can deform when the temperature rises; wherein, when the temperature drops, the shape memory metal sheet 21 will gradually recover its deformation to a straight shape.

[0039] like Figure 4 , Figure 5 As shown, in some embodiments, an annular receiving groove 13 is provided on the outer wall of the sealing lip 1; an annular elastic member 14 is sleeved inside the annular receiving groove 13, so that the inner wall of the sealing lip 1 abuts against the central shaft 4 to seal.

[0040] In this embodiment, the annular elastic element 14 is tightly clamped to the outside of the sealing lip 1, so that the sealing lip 1 always remains against the central shaft 4, thus avoiding the sealing failure caused by the gap between the sealing lip 1 and the central shaft 4 due to friction or other reasons.

[0041] like Figure 5As shown, in some embodiments, when forming the straight return oil line 2, the tilt angle α of the shape memory metal sheet 21 is between 45-60°; and the distance H1 between the inner end 212 of the shape memory metal sheet 21 and the lip 15 of the sealing lip 1 is between 0.5-1.5 mm.

[0042] In this embodiment, H1 is located at 0.5-1.5mm in order to make the pump suction of the straight oil return line 2 closer to the lip 15 of the sealing lip 1.

[0043] like Figure 6 As shown, in some embodiments, when forming the wavy return oil line 3, the distance H2 between the inner peak 213 of the shape memory metal sheet 21 and the lip 15 of the sealing lip 1 is 2-5 mm.

[0044] In this embodiment, H2 is located at 2-5 mm to prevent cracked material from accumulating on the lip 15 of the sealing lip 1.

[0045] like Figure 6 As shown, in some embodiments, a dustproof lip 5 is provided on the outer side of the sealing lip 1; a gear oil storage cavity 6 is formed between the dustproof lip 5 and the sealing lip 1.

[0046] like Figure 7 As shown, at least one embodiment also provides a forklift differential, including: a differential body 7 having a mounting hole for a motor shaft to pass through; and an oil seal for the forklift differential disposed in the mounting hole of the differential body 7.

[0047] For the specific structure and implementation process of the oil seal for the forklift differential, please refer to the relevant discussion in the above embodiments, which will not be repeated here.

[0048] In this embodiment, the motor 8 serves as a power source, and its motor shaft extends into the differential body 7 and passes through the oil seal. The motor shaft rotates to drive the gear meshing with it to rotate.

[0049] At least one embodiment also provides a method for operating an oil seal for a forklift differential, comprising: a plurality of inclined shape memory metal sheets 21 are uniformly arranged along the circumference of the first inclined surface 11 of the sealing lip 1 to form a straight oil return line 2; when the temperature of the gear oil rises, each shape memory metal sheet 21 deforms to connect adjacent shape memory metal sheets 21 end to end to form a wavy oil return line 3.

[0050] For the specific structure and implementation process of the oil seal for the forklift differential, please refer to the relevant discussion in the above embodiments, which will not be repeated here.

[0051] In some embodiments, when the temperature of the gear oil rises, the method of forming a wavy oil return line 3 by deforming adjacent memory metal sheets 21 to connect them end to end includes: connecting the middle part 211 of the memory metal sheet 21 to the first inclined surface 11; when the temperature of the gear oil rises, the memory metal sheet 21 forms an "S" shape by bending the two ends in opposite directions.

[0052] In some embodiments, when the temperature of the gear oil rises, the method of forming a wavy oil return line 3 by deforming adjacent memory metal sheets 21 to connect them end to end.

[0053] In some embodiments, the method of forming an "S" shape by bending the memory metal sheet 21 in the opposite direction at both ends when the temperature of the gear oil rises includes: when the temperature of the gear oil rises, both ends of the memory metal sheet 21 are bent inward to form an "S" shape.

[0054] In summary, the working method of the oil seal in this forklift differential uses a shape memory metal sheet 21 as the oil return line. When the temperature rises, the shape memory metal sheet 21 deforms, changing from a straight oil return line 2 to a wavy oil return line 3, allowing the gear oil to flow along the wavy oil return line 3. Under this flow mode, cracked products are less likely to accumulate at the lip. The reason why this solution does not directly use the wavy oil return line 3 is that the back suction efficiency of the straight oil return line 2 is more stable in low-temperature scenarios.

[0055] In this document, when it is said that the first component is located on the second component, this can mean that the first component can be directly formed on the second component, or that the third component can be inserted between the first component and the second component.

[0056] In this document, when an element or layer is referred to as “located,” “joined to,” “connected to,” “attached to,” or “coupled to” another element or layer, it may be directly located, joined, connected, attached to, or coupled to the other element or layer, or there may be intermediate elements or layers present. Conversely, when an element is referred to as “directly on another element or layer,” “directly joined to,” “directly connected to,” “directly attached to,” or “directly coupled to” another element or layer, there may be no intermediate elements or layers present. Other terms used to describe relationships between elements should be interpreted in a similar manner (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and / or” includes any and all combinations of one or more of the related listed items.

[0057] The terminology used herein is for the purpose of describing specific exemplary configurations only and is not intended to be limiting. As used herein, the singular articles “a,” “an,” and “the” may also be intended to include plural forms unless otherwise clearly stated herein. The terms “comprising,” “including,” and “having” are inclusive and thus specify the presence of features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein should not be construed as requiring them to be performed in the specific order discussed or shown, unless specifically identified as such. Additional or alternative steps may be employed.

[0058] In the description of this invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0059] Spatially relative terms, such as “inside,” “outside,” “below,” “below,” “down,” “above,” “up,” etc., may be used herein to describe the relationship between one element or feature illustrated in the figures and another element or feature. In addition to the orientations depicted in the figures, spatially relative terms may be intended to cover different orientations of the apparatus in use or operation.

[0060] In the above discussion, unless otherwise stated, when used to describe numerical values, the terms “about,” “approximately,” “basically,” etc., indicate a change of + / - 10% in that value.

[0061] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. An oil seal for a forklift differential, characterized in that, include: The sealing lip (1) has an inner wall comprising: a first inclined surface (11) and a second inclined surface (12); A plurality of shape memory metal sheets (21) are provided, each of which is inclined and evenly distributed along the circumference of the first inclined surface (11) to form a straight oil return line (2); wherein The middle part (211) of the memory metal sheet (21) is fixedly connected to the first inclined surface (11), and the two ends of the memory metal sheet (21) are not fixed. When the temperature of the gear oil rises, the two ends of the memory metal sheet (21) bend in opposite directions to form an "S" shape, and the adjacent memory metal sheets (21) are connected end to end to form a wavy oil return line (3), so that the gear oil flows along the wavy oil return line (3).

2. The oil seal for a forklift differential as described in claim 1, characterized in that, The outer wall of the sealing lip (1) is provided with an annular receiving groove (13); The annular receiving groove (13) is fitted with an annular elastic element (14) so ​​that the inner wall of the sealing lip (1) abuts against the central shaft (4) to seal.

3. The oil seal for a forklift differential as described in claim 2, characterized in that, When forming a straight return oil line (2), the tilt angle α of the shape memory metal sheet (21) is between 45° and 60°; and The distance H1 between the inner end (212) of the memory metal sheet (21) and the lip (15) of the sealing lip (1) is 0.5-1.5 mm.

4. The oil seal for a forklift differential as described in claim 3, characterized in that, When forming the wavy return oil line (3), the distance H2 between the inner peak (213) of the memory metal sheet (21) and the lip (15) of the sealing lip (1) is 2-5 mm.

5. The oil seal for a forklift differential as described in claim 1, characterized in that, A dustproof lip (5) is provided on the outer side of the sealing lip (1); A gear oil storage cavity (6) is left between the dustproof lip (5) and the sealing lip (1).

6. A forklift differential, characterized in that, include: The differential body (7) has a mounting hole for the motor shaft to pass through; as well as The oil seal for the forklift differential as described in any one of claims 1-5 is disposed in the mounting hole of the differential body (7).

7. A method for operating an oil seal for a forklift differential as described in any one of claims 1-5, characterized in that, include: On the first inclined surface (11) of the sealing lip (1), several inclined shape memory metal sheets (21) are evenly arranged circumferentially to form a straight oil return line (2); among them The middle part (211) of the memory metal sheet (21) is fixedly connected to the first inclined surface (11), and the two ends of the memory metal sheet (21) are not fixed; When the temperature of the gear oil rises, each memory metal sheet (21) bends in the opposite direction at both ends to form an "S" shape, so that adjacent "S" shaped memory metal sheets (21) are connected end to end to form a wavy oil return line (3).

8. The working method of the oil seal for a forklift differential as described in claim 7, characterized in that, The method of forming an "S" shape by bending the shape memory metal sheet (21) in the opposite direction at both ends when the temperature of the gear oil rises includes: When the temperature of the gear oil rises, both ends of the memory metal sheet (21) bend inward to form an "S" shape.

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